Competitor's Design
As oil flows out of the accumulator, the bladder comes in contact with the poppet at the bottom of the accumulator. The bladder starts to close the poppet which is being held open by a spring.

The bladder wraps around the poppet and forces the oppet down. Then the poppet closes on the bladder, causing a cut which results in accumulator failure. The above photograph illustrates how the bladder can flow under the poppet while fluid is flowing out of the accumulator.